Wilhelm von Keppel (Kepfel, a parish in the duchy of Berg, Germany), was an early Anabaptist and a former Catholic priest. He may have been a preacher (Mennonitisches Lexikon II, 482), but there is no proof for this assertion, nor is there information as to the time of his uniting with the Anabaptist congregation. While he was a member he worked at his trade of buckle-making (Krampenmacher) in the duchy of Berg, now in the Rhine-Wupper district. In 1561 he was arrested ("a priest, Wilhelm Keppel by name") with a large number of the Anabaptist congregation of Cologne. Only those were punished who refused to recant. Wilhelm von Keppel was arrested the second time in 1562, and must therefore have been released after the first arrest, which indicates that he had recanted. After his second arrest he was imprisoned in one of the towers of Cologne, where he was subjected to torture before he was transferred to the dungeon in September 1562, which was the prison of the Supreme Court of Cologne. He was placed into a cell already occupied by the Anabaptist Georg Friesen. Both were tortured here in an attempt to convince them of the correctness of infant baptism. In his cross-examination Wilhelm declared that "he did not regard the ceremonies of the church as anything, considered the Catholic worship useless, the devil was the teacher of the Catholics, only God's Word, and by no means the doctrines of men should be obeyed." But neither the rack, threats, nor any other attempts at conversion induced him or Georg Friesen to recant, and they were consequently sentenced to death by drowning. After the waters of the Rhine had closed over Georg Friesen, Wilhelm declared himself willing to recant. Thereupon he was banished from the city and region (Turmbuch No. 2, p. 98; Ennen, 815, note 2): "Wilhelm Krampenmacher of Monheim banished and condemned by the Grefenand bailiffs of the city and the archbishopric of Cologne; because he would be submerged in a boat with Georg, and feared death, he said that he would desist from his error."

Their imprisonment and the martyrdom of Friesen, Keppel later described in a song which is found in the Ausbund (No. 22, p. Biff.), but which is true to fact only in so far as it refers to Georg Friesen, since he denies the recantation he made. Another account of these men is found in the Martyrs Mirror, which in some respects contradicts the account given in the poem. The reason for the errors in the reports is not yet clear.

In the song, Wilhelm von Keppel closes with admonitions to his brethren and sisters, poses as their defender, who "has fought with lions wild and with wolves" (stanza 34), and in stanza 35 he cries out to them—ambiguously—"Therefore, dear brethren and sisters mine, prepare yourselves with diligence, that you may also be qualified to fight with such a foe." Was he alluding to the qualifications of Georg Friesen or his own? Why did he not rather maintain a humble silence

Braght, Thieleman J. van. The Bloody Theatre or Martyrs' Mirror of the Defenseless Christians Who Baptized Only upon Confession of Faith and Who Suffered and Died for the Testimony of Jesus Their Saviour . . . to the Year